"The financial results were impacted by external events, including supply constraints, which will subside in the second half, and a considerable increase in the cost of raw materials," said chief executive Carlos Ghosn.

He said in the statement the group maintained its outlook for operational free cash flow -- a key measure of profitability -- at more than €500 million this year.

"The supply constraints stemming from the Japanese tsunami had an unfavourable impact on the operating margin of automotive of an estimated €150 million in the first half," the statement said.

The company said it expected the consequences of the earthquake would cost it a further €50 million this year.

"Supply constraints are expected to subside gradually in the second half, enabling a strong recovery in production from September."